This adds the missing handling for defs for target index operands, as is
already done for registers.
There are two kinds of target indices: local indices and stack operands.
- Locals are something similar to registers in Wasm-land. For local
indices, we can check for local-defining instructions (`local.set` or
`local.tee`).
- Wasm is a stack machine, so we have values in certain Wasm value stack
location, which change when Wasm instructions produce or consume
values. So basically any value-producing instrucion, i.e., instruction
with defs, can change values in the Wasm stack. But I think we don't
need to worry about this here, because `WebAssemblyDebugFixup`, which
runs right before this analysis, makes sure to insert terminating
`DBG_VALUE $noreg` instructions whenever a stack value gets popped.
After `WebAssemblyDebugFixup`, there shouldn't be any `DBG_VALUE`s for
stack operands that don't have a terminating `DBG_VALUE $noreg` within
the same BB.
So this CL only works on `DBG_VALUE`s for locals. When we encounter a
`local.set` or `local.tee` instructions, we delete `DBG_VALUE`s for
those target index locations from the open range set, so they will not
be availble in `OutLocs`. For example,
```
bb.0:
successors: %bb.1
DBG_VALUE target-index(wasm-local) + 2, $noreg, "var", ...
...
local.set 2 ...
bb.1:
; predecessors: %bb.0
; We shouldn't add `DBG_VALUE target (wasm-local) + 2 here because
; it was killed by 'local.set' in bb.0
```
After disabling register coalescing at -O1, the average PC ranges
covered for Emscripten core benchmarks is currently 20.6% in the LLVM
tot. After applying D138943 and this CL, the coverage goes up to 57%.
This also enables LiveDebugValues analysis in the Wasm pipeline by
default.
Reviewed By: dschuff, jmorse
Differential Revision: https://reviews.llvm.org/D140373
This was stored in LiveIntervals, but not actually used for anything
related to LiveIntervals. It was only used in one check for if a load
instruction is rematerializable. I also don't think this was entirely
correct, since it was implicitly assuming constant loads are also
dereferenceable.
Remove this and rely only on the invariant+dereferenceable flags in
the memory operand. Set the flag based on the AA query upfront. This
should have the same net benefit, but has the possible disadvantage of
making this AA query nonlazy.
Preserve the behavior of assuming pointsToConstantMemory implying
dereferenceable for now, but maybe this should be changed.
DwarfDebug unconditionally assumes for all call instructions the 0th
operand is the callee operand, which seems to be true for other targets,
but not for WebAssembly. This adds `TargetInstrInfo::getCallOperand`
method whose default implementation returns `getOperand(0)` and makes
WebAssembly overrides it to use its own utility method to get the callee
operand.
This also fixes an existing bug in `WebAssembly::getCalleeOp`, which was
uncovered by this CL.
Reviewed By: dschuff, djtodoro
Differential Revision: https://reviews.llvm.org/D102978
Extends DWARF expression language to express locals/globals locations. (via
target-index operands atm) (possible variants are: non-virtual registers
or address spaces)
The WebAssemblyExplicitLocals can replace virtual registers to targertindex
operand type at the time when WebAssembly backend introduces
{get,set,tee}_local instead of corresponding virtual registers.
Reviewed By: aprantl, dschuff
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D52634
MachineInstr.h included AliasAnalysis.h, which includes a world of IR
constructs mostly unneeded in CodeGen. Prune it. Same for
DebugInfoMetadata.h.
Noticed with -ftime-trace.
llvm-svn: 375311
Summary:
Uses the named operands tablegen feature to look up the indices of
offset, address, and p2align operands for all load and store
instructions. This replaces brittle, incorrect logic for identifying
loads and store when eliminating frame indices, which previously
crashed on bulk-memory ops. It also cleans up the SetP2Alignment pass.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59007
llvm-svn: 355770
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr. This is a
general API improvement.
Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other. Instead I've done everything as a block and just
updated what was necessary.
This is mostly mechanical fixes: adding and removing `*` and `&`
operators. The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency. Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy. I couldn't run tests
for AVR since llc doesn't link with it turned on.
llvm-svn: 274189
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
This patch revamps the RegStackifier pass with a new tree traversal mechanism,
enabling three major new features:
- Stackification of values with multiple uses, using the result value of set_local
- More aggressive stackification of instructions with side effects
- Reordering operands in commutative instructions to enable more stackification.
llvm-svn: 259009
Teach the register stackifier to rematerialize constants that have multiple
uses instead of leaving them in registers. In the WebAssembly encoding, it's
the same code size to materialize most constants as it is to read a value
from a register.
llvm-svn: 258142
This pass implements a simple algorithm for conversion from CFG to
wasm's structured control flow. It doesn't yet handle multiple-entry
loops; that will be added in a future patch.
It also adds initial support for switch statements.
Differential Revision: http://reviews.llvm.org/D12735
llvm-svn: 247818
Summary:
Add a basic CodeGen bitcode test which (for now) only prints out the function name and nothing else. The current code merely implements the basic needed for the test run to not crash / assert. Getting to that point required:
- Basic InstPrinter.
- Basic AsmPrinter.
- DiagnosticInfoUnsupported (not strictly required, but nice to have, duplicated from AMDGPU/BPF's ISelLowering).
- Some SP and register setup in WebAssemblyTargetLowering.
- Basic LowerFormalArguments.
- GenInstrInfo.
- Placeholder LowerFormalArguments.
- Placeholder CanLowerReturn and LowerReturn.
- Basic DAGToDAGISel::Select, which requiresGenDAGISel.inc as well as GET_INSTRINFO_ENUM with GenInstrInfo.inc.
- Remove WebAssemblyFrameLowering::determineCalleeSaves and rely on default.
- Implement WebAssemblyFrameLowering::hasFP, same as AArch64's implementation.
Follow-up patches will implement a real AsmPrinter, which will require adding MI opcodes specific to WebAssembly.
Reviewers: sunfish
Subscribers: aemerson, jfb, llvm-commits
Differential Revision: http://reviews.llvm.org/D11369
llvm-svn: 242939
